This invention relates to a telescopic gun sight. Such sights in various forms are well known in the art.
In typical telescopic sights of the prior art, there is a tubular telescope attached to the gun barrel. The telescope has an objective and an eyepiece or ocular. The target is imaged in the plane of the objective in laterally reversed and upside down orientation. An optical inverting system arranged within the tubular housing serves to erect the image and images it in the plane of the eyepiece, where it is viewed by the eyepiece.
In order to estimate the distance away of the object or sighted target, there is a reticle (a grid of crossed lines) mounted in the objective or eyepiece image plane, in the telescopic gun sights of known construction. In order to obtain a variable magnification, the optical elements of the inverting system of the known sights are made displaceable, and the point of attack or point of action of the displacement device is located in the vicinity of the objective image plane, the necessary path of displacement resulting from the angle of the target line displacement multiplied by the focal length of the objective. In order to change the target line (that is, to make necessary lateral and vertical corrections in the line of sight relative to the gun barrel on which the telescopic sight is mounted to compensate, respectively, for such variables as windage and the effect of gravity on bullet trajectory), it is furthermore known to mount the inverting system tiltably so as to be movable toward all sides in the telescope tube. Such known tiltable inverting systems are often organized within an auxiliary tube pivotally mounted at one end, the pivotal mounting being in the form of a circular or spherical bearing, or comprising a support surface made from an elastomer or other resilient material. It is also known to shift the pivot point of the tilting into the eyepiece image plane.